The Short Answer Educational content only. Any suspected concussion warrants medical evaluation. New, severe, or changing headache after head injury warrants prompt assessment by a physician, neurologist, or headache specialist to confirm the diagnosis and exclude dangerous causes. Consult a concussion-experienced clinician for individualized care. Concussion can trigger paroxysmal hemicrania, a trigeminal autonomic cephalalgia of frequent, short, severe one-sided attacks with autonomic features that responds completely to indomethacin (Ashina et al., 2019). Paroxysmal hemicrania produces multiple daily attacks of severe one-sided pain around the eye or temple, each lasting only minutes, with same-side autonomic signs such as tearing and nasal congestion. Its many brief attacks distinguish it from cluster headache, and like hemicrania continua it responds absolutely to indomethacin, which defines and treats it. After trauma, disruption of the trigeminal-autonomic pathways can produce this pattern. Recognizing it prompts an indomethacin trial that typically resolves the attacks. Paroxysmal hemicrania is frequent, short, severe one-sided attacks with autonomic features. Its many brief daily attacks distinguish it from cluster headache. It responds completely to indomethacin, which confirms and treats it. What Paroxysmal Hemicrania Is Paroxysmal hemicrania is one of the trigeminal autonomic cephalalgias, closely related to cluster headache but with a distinct rhythm. It produces attacks of severe, strictly one-sided pain centered around the eye, temple, or forehead, accompanied by same-side autonomic features, tearing, redness, nasal congestion or running, and sometimes eyelid changes. Each attack is short, typically lasting 2 to 30 minutes. The defining feature is frequency. Attacks occur many times a day, often more than five and sometimes dozens, day after day. This high frequency of short attacks separates paroxysmal hemicrania from cluster headache, which produces fewer, longer attacks. The combination of many brief severe one-sided attacks with autonomic signs is the recognizable pattern. The Defining Indomethacin Response Like hemicrania continua, paroxysmal hemicrania responds completely and specifically to indomethacin, and this absolute response is part of its diagnostic definition. An adequate dose of indomethacin abolishes the attacks, and this response is so characteristic that a supervised trial serves as a diagnostic test. Complete resolution confirms paroxysmal hemicrania, while failure to respond points toward cluster headache or another diagnosis. This indomethacin sensitivity is clinically important because it separates paroxysmal hemicrania from cluster headache, which it can resemble. Cluster headache does not respond to indomethacin in this way, so the medication both distinguishes the two disorders and provides highly effective treatment for paroxysmal hemicrania. Missing the diagnosis means missing a specific, often complete, treatment. How Concussion Can Trigger It Head trauma is a recognized trigger for paroxysmal hemicrania. The injury can disrupt the trigeminal-autonomic pathways whose activation generates the short severe attacks and their autonomic features. Post-traumatic paroxysmal hemicrania appears after the injury and carries the same defining characteristics, including the frequent short attacks and the indomethacin response. As with the related trigeminal autonomic cephalalgias, the specific phenotype reflects involvement of these particular pathways, producing a recognizable and specifically treatable headache rather than a nonspecific post-traumatic ache. Symptom Presentation Severe, strictly one-sided pain around the eye, temple, or forehead Short attacks lasting roughly 2 to 30 minutes Many attacks per day, often more than five Same-side autonomic features: tearing, redness, nasal congestion, eyelid changes Attacks recurring day after day Onset after a head injury Complete resolution on an adequate dose of indomethacin Assessment A neurologist or headache specialist recognizes the pattern of frequent short one-sided attacks with autonomic features and arranges a supervised indomethacin trial, which confirms the diagnosis when the attacks resolve. Because a secondary cause can rarely mimic the disorder, particularly after head injury, brain imaging is generally obtained to exclude a structural lesion. The specialist distinguishes paroxysmal hemicrania from cluster headache by attack frequency and duration and by the indomethacin response, and from SUNCT by attack length and autonomic pattern. Treatment Approach Indomethacin is both the diagnostic test and the treatment. An adequate dose typically abolishes the attacks, and the clinician then establishes the lowest effective maintenance dose. Because indomethacin can affect the stomach and kidneys, it is used with gastric protection and monitoring under specialist guidance. Some people need it long term, while others can reduce or stop it after a period. For those who cannot tolerate indomethacin, a specialist considers alternatives, though none is as reliably effective. Addressing coexisting contributors, the cervical component, sleep, and autonomic regulation, supports overall stability, and avoiding medication overuse protects against a superimposed daily headache. The essential step remains recognizing the frequent short attack pattern and trialing indomethacin, which often produces complete relief. Post-traumatic headache often has a cervical and autonomic component that responds to daily mobility and nervous system regulation alongside medical care. Start your 3-day free trial to build a supportive routine. Supporting Mobility Routine JME 155 Diaphragmatic breathing lowers the sympathetic drive that fuels headache and supports steady cerebral blood flow. Ten slow breaths, several times daily. JME 14 Chin tucks activate deep cervical flexors and reduce the upper cervical tension that refers pain to the head. Ten repetitions with 5-second holds. JME 1 Cervical rotation restores segmental mobility at the joints that refer pain into headache through the trigeminocervical nucleus. Ten repetitions per direction. JME 15 Cervical lateral flexion addresses side-bending restriction that sustains neck-driven headache. Ten repetitions per side. JME 16 Cervical flexion and extension restore sagittal mobility restricted by suboccipital guarding. Eight slow repetitions. JME 2 Cervical retraction reinforces a neutral head position that reduces the postural strain feeding headache. Ten repetitions per set. JME 150 Thoracic rotation restores mid-back motion needed for full cervical range and relaxed upright posture. Eight repetitions per direction. JME 227 Overhead reach opens the thoracic spine and reduces the compensatory upper cervical extension that drives headache. Ten repetitions with controlled tempo. Start your 3-day free trial for joint-specific mobility programming that addresses the cervical and autonomic contributors to post-traumatic headache. Common Mistakes Mistaking paroxysmal hemicrania for cluster headache and missing the indomethacin response Never arranging the indomethacin trial that confirms and treats it Using indomethacin without gastric protection and monitoring Overlooking a structural cause after head injury before the trial Allowing medication overuse to add a daily headache Progression A specialist recognizes the frequent short one-sided attacks with autonomic features, excludes a structural cause, and arranges a supervised indomethacin trial. Complete resolution confirms the diagnosis and establishes treatment at the lowest effective dose under monitoring. Cervical, sleep, and autonomic support supplement care. Some people need indomethacin long term, while others reduce it after a period. What is paroxysmal hemicrania? It is a trigeminal autonomic cephalalgia of frequent, short, severe one-sided attacks around the eye or temple with same-side autonomic features. Attacks last minutes and occur many times a day. Like hemicrania continua, it responds completely to indomethacin, which is part of its diagnostic definition. How is paroxysmal hemicrania different from cluster headache? Paroxysmal hemicrania produces more frequent, shorter attacks, often many per day lasting minutes, and responds completely to indomethacin. Cluster headache produces fewer, longer attacks and does not respond to indomethacin in this way. The attack frequency, duration, and indomethacin response distinguish them, and the treatments differ. Can a concussion cause paroxysmal hemicrania? Head trauma is a recognized trigger. The injury can disrupt the trigeminal-autonomic pathways that generate the short severe attacks and their autonomic features. Post-traumatic paroxysmal hemicrania carries the same features as the primary form, including the frequent short attacks and the indomethacin response. Why does an indomethacin trial matter? Paroxysmal hemicrania responds completely to indomethacin, so a supervised trial confirms the diagnosis and provides the treatment at once. It also separates the disorder from cluster headache, which it resembles but which does not respond to indomethacin. Missing the trial means missing a specific, often complete, treatment. Is treatment lifelong for paroxysmal hemicrania? Not always. Indomethacin controls the attacks, and a specialist maintains the lowest effective dose with monitoring for stomach and kidney effects. Some people need it long term, while others can reduce or stop it after a period. A specialist guides the duration based on the individual course. Red Flags Requiring Urgent Evaluation The following warrant same-day emergency evaluation rather than routine care. Sudden severe headache that peaks within seconds to minutes Headache with fever, neck stiffness, or rash New weakness, numbness, slurred speech, or facial droop New vision loss, double vision, or a persistent visual change Progressive worsening headache over days to weeks Headache with confusion, drowsiness, or repeated vomiting Headache with seizure or loss of consciousness Sudden severe neck pain with neurological symptoms, suggesting arterial dissection These features can indicate a dangerous cause and take priority over any headache-specific diagnosis. Absence of red flags supports outpatient evaluation and management. Medication Overuse Headache Frequent use of acute headache medication can produce medication overuse headache, where the treatment itself sustains a daily or near-daily headache. This is common after concussion, when frequent pain drives frequent medication use. As a general guide, using simple analgesics on 15 or more days per month, or triptans, combination analgesics, or opioids on 10 or more days per month, raises the risk. Preventive treatment and careful limits on acute medication, guided by a clinician, break the cycle. Recognizing medication overuse is essential, because it can mimic or worsen any post-traumatic headache pattern. Why a Precise Diagnosis Matters Post-traumatic headache is not one condition. It takes on the features of recognized primary headache disorders, and each has a specific, sometimes highly specific, treatment. Some headaches respond dramatically to one particular medication, others need targeted preventives, and others improve with cervical and autonomic treatment. A precise diagnosis by a physician, neurologist, or headache specialist, using the criteria of the International Classification of Headache Disorders, directs the person to the treatment most likely to work and avoids prolonged trial and error. Multidisciplinary Care and the Cervical Contribution Post-traumatic headache frequently has more than one driver. A cervical contribution from the neck is common, since the upper cervical joints and nerves refer pain to the head through the trigeminocervical nucleus, the same brainstem region where neck and head pain signals converge. Autonomic dysregulation, sleep disturbance, mood, and medication overuse each add to the picture. Coordinated care works best: a headache specialist or neurologist for diagnosis and medication, a physical therapist for the cervical and postural contribution, and attention to sleep, mood, and autonomic regulation. Treating the neck and nervous system alongside medical management improves many post-traumatic headaches that medication alone does not fully control. References Ashina, H., et al. (2019). Post-traumatic headache: epidemiology and pathophysiological insights. Nature Reviews Neurology, 15(10), 607-617. PubMed Headache Classification Committee of the International Headache Society (IHS). (2018). The International Classification of Headache Disorders, 3rd edition. Cephalalgia, 38(1), 1-211. PubMed Patricios, J. S., et al. (2023). Consensus statement on concussion in sport: the 6th International Conference on Concussion in Sport, Amsterdam, October 2022. British Journal of Sports Medicine, 57(11), 695-711. PubMed